Electric furnace



Jan. 1, 1929.

J. c. wooDsoN ELELCERIC FURNACE Original Filed Feb. 10, 1925 INVENTORJames C Wooa'san WITNESSES: 5.96

ATTORNEY Patented Jan. 1929.

UNITED STATES PATENT OFFICE.

J'AIES G. WOODSON, OF EAST PITTQiUBG-H; PENNSYLVANIA, ASSIGNOR '10was'rme- HOUSE We. & mU I'LCTURIHG QQKPA N Y, A CORPORATION 01 Imam.

VANIA.

EEC-ERIC FURNACE.

Application fled February 10, ms, semi I... a,2a4. Renewed October as,me.

My invention relates to electric furnaces and particularly to means forsupporting electric resistor units in electric furnaces.

One of the-ob'ects of myinvention is to provide means or supportingelectric resistor units in an electric furnace in such manner. thattheyare maintained in spaced relation relatively to the cooperatingwalls of said furnace.

vide means for sup rting electric furnace resistor units in sucmanner-that they are interlocked in operative position.

A still further object of my invention to provide means for supporting aplurality of electric furnace resistor units in such manner that doublebanking of the units may be obtained.

In practicing my invention, .1 provide an electric furnace chamberhaving the usual side and bottom walls and that is especially adaptedfor use in' melting materials having relatively low meltingtemperatures. A suitable container of ceramic or other refractorymaterial is provided, so shaped that it is suprted in spaced relation,relatively'to t e ottom'wallsof the furnacew :A plurality of refractoryresistor unit. sup orting members are supported by the s1 e and bottomwalls of the furnace and comprises a substantiall straight member thatis secured in any well known mannerto the supporting wall.

The resistor-unit supporting members employed .in the bottom'wa'll ofthe furnace chamber are so constructed that the resistor units su rtedthereby are maintained in skeletone s aced relation from each other and"at a desire 1e distance above the bottomwall structure. By. supportingthe resistors above the bottom wall in this manner, molten materialwhich may leak through cracks or crevices in the container, which maydevelo therein from intermittent heating and coo 48 ing thereof or othercauses, will pass through v the resistors without solidifyingtherearound.

The slope of the bottom wall structure is so arranged that any moltenmaterialthatmay fall, into the furnace chamber willflo'w' to- It. wardsa convenient opening therein through which it may be drained. 1

The refractory members have a plurality of integral, oppositelextending, transverse flanges between whic cooperatm pairs of 66.slotted refractory members exten and are Another object of my inventionis to pro-V transverse supported thereby. The slotted refractory membersare adapted to receive an electric resistormember and tointerlocktherewith in operative positionin a manner hereinafter morefully described.

' Inthe drawing,

' Figure 1 is a front elevational view, partially in section, of anelectric furnace embodying my invention;

Fig. 2 is a fragmentary front elevational view of an electric resistorunit supporting member and an electric-resistor unit cooperatintherewith; i

ig. 3 is a top plan view thereof; and I Fig. 4 is a front elevationalview of one-of the refractory members comprised in the resistor unitembodying my invention.

An electric furnace represented by the numeral 11 comprises a verticalwall 12 and a bottom wall 13 enclosing a furnace chamber 14. A materialreceiving means 15 is supported in any suitable manner, but I havepreferred to show a member having a substantially cup-shaped'portionhaving outwardly extending flan e portions 16 to cooperate with the top0 the wall 12 to support the same inspaced relation relatively to thebottom wall 13 of the furnace chamber 14.

The upper surfacemf the bottom wall 13 is inclined towards the centerthereof to permit draining of an 7 molten material that may leak throughrom the-material receiving means15. A drain 17 is provided at the centerof the bottom 13 and may be of any suitable construction as itconstitutes no part of my invention.

A plurality of resistor unit supporting means 18 and 1811 are supportedin any suitable manner b the walls 12 and 13 r tivelfyl and exteninwardl therefromanto the mace chamber 14. 'll he resistor unitsupporting members 18 comprise a substantially straight ortion 19 thatis secured in the furnace wal 12. The supporting members 180 comprise aplurality o oppositely extending anges 21 and a straight portion 19a;The resistor unit sup rting means '18 and 18a may be constructed of anysuitable refractory material eithermetallic or ceramic. The transverseflanges 21 are located .in spaced relation relatively to the walls 12and 13 of the furnace chamber and are adapted to support a plurality ofrefractory members 22. z

The refractory members 22 have a plurality of transverse slots 24 thatare adapted to receive a resistor member 25. The refrac- Y Y pin members26 that are located in abutting relation thereto, whereby lateralmovement relatively to the resistor unit supporting member is prevented.

The supporting members 18a located in the bottom wall 13 of the furnacechamber maybe so'arranged that the refractory members 22 are supportedat a desirable distance thereabove. Since the members 22 are locatedabove the inclined wall 13, the resistor members 25 that are supportedthereby will not come in contact with molten metals or the like that mayflow "along said wall so as to cause a short circuit thereof.

It is evident from Fig. 3, that, if the memibBIS 18a are located inabutting relation to each other in the inclined wall 13 of the furnacechamber 13, a clearance space (not shown) between the refractory members22 will be provided,-because the flanges 21 extend beyond the members 22on both sides thereof. If metal or other molten substances contained inthe material-receiving means 15.

should'acc'identally leak into the chamber 14, it will pass through theclearance spaces referred to above without collecting around-theresistor members so as to cause a short-circuit thereof. It is highlydesirable to prevent a short-circuit of this nature because theresistors usually employed in electric furna'ces are very expensive andare therefore worthy of protection.

The resistor members 25 which are supported by the refractory members 22have sufiicient stiffnessand stren h to maintain themselves in asubstantia ly straight-line condition even when the members 22 arespaced at relatively great distances apart as compared with thedimensions of the resistor members 25. By spacing the refractory members18a at suitable distances apart in accordance with the weight anddimensions of the resistor members 25, the heating units may be made asopen and skeleton-like as desired.

' The slots 24 of the refractory members 22 are located in corres ondingfaces" thereof, thereby simplifyin the assembly of resistor units as'these mem ers are substantially similar and interchangeable. In the.particular embodiment of my invention illustrated in Figs. 2 and 3,I-have shown two independent rows or banks 23 and 23a of the members 22operatively engaging the resistor members 25 and a resistor member 28.Each of the rows 01 banks 23 and 23a comprises a pair of members 22located in side-"by-side relation operatively engaging a resistor member25 8.114128, respectively. The resistor members 25 and 28 are supportedby the members 22 in which the slots 24 extend upwardly and aremaintained in this position by the members 22 which partially enclosethe resistor from above and in which the slots 24 thereof extenddownwardly. The effect of the slots 24 of the refractory members 22 inenclosing the resistor members 25 and 28 from opposite directions is tointerlock the members together, thereby preventing lateral movement ofthe resistor member 25 relatively to the refractory members 22. 1

Although I have shown a. furnace structure of a type suitable for use inmelting low temperature materials, I do not wish to be such mannerthat aplurality of resistor members may be supported thereby. Another pair ofrefractory members 22 are located transversely between-the resistor unitsupporting members 18a and secured thereto beneath the refractorymembers 22. The refractory members 22 interlock in operative positionwith the resistor member 28 in the manner hereinbefore described wherebya double banking of resistor members is thereby obtained.

My invention is.closel related to the co-' pending application of D.Keene, Serial No. 4,236, filed Jan 23, 1925, which is assigned to theWestinghouse Electric and Manufacturing Company.

Various modifications and changes maybe made without departing from thespirit and scope of the invention, therefore I desire that only suchlimitations shall be placed thereon as are imposed by the prior art orare set forth in the appended claims. 2

I claim as my invention:

1. In an electric furnace, the combination with a plurality of wallsenclosing a furnace chamber, and a resistor unit supporting membersupported by the bottom wall of said furnace, of a plurality ofindependent resistor members supported by said supporting member insubstantially parallel rows and in open, skeleton-like spaced relationabove said bot tom wall and comprising a plurality of refractory membersinterlocked with said electric resistor members.

\ 2. Inan electric furnace, the combination with a furnace chamber and amaterial-receiving container supported therein, of a plurality ofresistor elements in said chamber,-

and means carried by the floor of said chamber for supporting saidresistor elements in spaced skeleton-like formation beneath. saidcontainer and spaced from the floor and side walls of said chamber, fl

In an electric furnace, the combination with a plurality of wallsdefining a furnace chamber, the bottom wall of said chamber being slopedtoward the center thereof to form a trough-like depression, amaterial-receivin receptacle within said chamber and suppo by the sidewalls thereof, of a plurality of re- ,sistor units within said chamber,and means severally carried bythe sloping portions of said bottom wallfor supporting said resistor ring inj u units beneath saidmaterial-receiving receptacle and in spaced relation to the bottom andside walls of said furnace chamber.

4(111 an electric furnace, the combination with a plurality of wallsdefining a furnace chamber, of a material-receiving receptacle withinsaid chamber suspended from the side walls thereof, of a plurality ofelectrical re-;

sistor heating units within said chamber beneath said receptacle, andmeans for preventfrom sai receptacle comprising a luralitiy of supportsseverally carried by, an exten ing above, the floor of said furnace,said supports being arranged to maintain said resistor units inopenskeleton-like formation and s aced from the floor and side walls ofsaid c amber.

5.,v In an electric furnace, the combination with a plurality ofrefractory walls enclos ing a furnace chamber, and a material-receivingmeans adapted to contain molten metals therein located in said'furnacechamber, of means for supporting a plurality of independent resistormembers in parallel rows and in skeleton-like formation above a bottomwall of said chamber, to permit molten metals leaking from said materiaIreceiVing means into said chamber to pass between said resistor members,v v 6; In an electric furnace, the combination with a plurality ofrefractory walls; enclosing a furnace chamber, and a material-receivingmeans adapted to contain molten metals therein located in said furnacechamber, of means for supporting a plurality of independent resistormembers in parallel rows and in skeleton-like formation above a bottomwall of said chamber comprisin a refractory member having a substantialstrai ht portion, one end of which is locate in sai bottom wall, andhaving a plurality of opposed laterally-extending flanges located at theother end of said straight portion which extends above said bottom wall.i

7. In an electric furnace, the combination with a plurality ofrefractory walls enclosing a furnace chamber, and a material-receivingmeans adapted to contain molten metals to said resistor units by leakagetherein located in said furnace chamber, of means for supporting aplurality of independent resistor members in parallel rows andinskeleton-like formationabove a bottom wall of said chamber comprisinga plugrality of refractory members having slots therein, said refractorymembers being located in pairs in side-by-side and in inverse relationto each other, one member of each of said pairs of refractory membershaving the slots therein extending upwardly for sup portingsaid'resistor members from substan-.

tially the underside thereof and the other member of each of said pairshaving the slots therein extending downwardly for re 'stering with saidresistor members from t e up-' per sidethereof.

& In an electric furnace, the combination ing pairs of refractorymembers extending v between said straight refractory members andsupported by said 9. In an electric furnace, the combination with aplurality of refractory walls enclosing a furnace chamber, and amaterial-receivi means adapted to contain molten metal therein locatedin said furnace chamber, of means for supporting a pluralit ofindependent resistor members 1n pa el rows and in skeleton-likeformation above a bottom wall of said chamber comprisi a refractorymember having a-substantia y straight r-, tio'n, one end of which islocated in said ttom wall and having a plurality of opppseda t onlaterally extendin flan ges integral with located at the other end ofsaid straight porfizion which extends above said bottom wa v 10. In anelectric furnace, the combination with a plurality of walls enclosing afurnace chamber, the surface of the bottom wall of said chamber slopingtowards the center thereof, a material-receiving means sufpported insaid chamber, and a plurality o resistor members associated with saidfurnace chamber, of means for supportingcertain of said resistor membersin an open; skeletonlike spacedrelatiorTabove the surface of an bottomwall.

11. In an electric furnace, the" tion with aplurality of walls enclosingafurenaoe chamber, the surface of thebottom wall thereof sloping towardsa drain located at the center thereof, a material-receiving meanslocated in said chamber and supported by said walls, and a plurality ofindependent resistor members associated with said chamber, of

means for supporting several of said resistor members in substantiallyparallel rows and in open skeleton-like formation above said bottomwall.

12. In an electric furnace, the combination with a plurality of wallsenclosing a furnace chamber, the surface of the bottom wall thereofsloping toward a drain located there mouse in, a material-receivingmeans located in said chamber and supported by said walls, and aplurality of independent resistor members associated with said chamber,of means for supporting several of said'resistor members insubstantially parallel rows and in open skelleton-like' formation abovesaid bottom Wa l.

In testimony whereof, I have hereunto subscribed my name this 9th day ofFebruary, 1925.

JAMES C. WOODSON.

